<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
   
</head>
<body>
    <h1>文档在脚步执行结束后加载</h1>
    <!-- 需要在放在body标签内部，最下面即可 -->
    <script>
        alert("放在body之后的脚步后执行")
    </script>
</body>

</html>